Q. WILL IT WORK IN AREAS THAT EXPERIENCE SUB-ZERO TEMPERATURES?
In most cases, yes. These temperatures won't stop the unit from working, however the amount of hot water it produces each hour will slow down slightly. To dramatically impact the performance of the unit, the temperature would need to remain below zero for extended periods of time, which is not a common occurence in most parts of Australia.
Also thanks to it's Active Defrost feature, this will protect the unit from frost build up to ensure it gets back to generating hot water.